Great AP rundown of how good samaritans used cutting-edge tech to bring voice and data to areas hit by Katrina: Of course, FEMA got in the way, even of groups connected with the military. Government and emergency coordination seems practically non-existent, as most other reports have confirmed, so these on-the-ground volunteers just went out and did what was needed to bring communications to hospitals and evacuation centers. Companies opened their warehouses--I'd heard this from other sources, too--and sent whatever was needed.
The efforts included pre-WiMax, self-healing mesh, VoIP, and satellite uplinks mostly combined with Wi-Fi on the local link. Of course, smaller groups are fleeter than bureaucracies, but there's something a little ridiculous in how quickly and easily these connections were set up. NASA apparently decided that small missions could achieve more discrete goals more readily; perhaps emergency response needs to organize into big and small cells to allow more discrete tasks to happen with less overhead.